Ignore jumps that have side effects in loop processing as pasting the 
body of a loop multiple times within is semantically equivalent to jump 
deletion (between the iterations unrolled) even if we do not physically 
delete the jump RTL insn.

        gcc/
        * loop-iv.c (simplify_using_initial_values): Only process jumps 
        that match `onlyjump_p'.
        (check_simple_exit): Likewise.
---
 gcc/loop-iv.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

gcc-loop-iv-only-jump.diff
Index: gcc/gcc/loop-iv.c
===================================================================
--- gcc.orig/gcc/loop-iv.c
+++ gcc/gcc/loop-iv.c
@@ -1936,7 +1936,7 @@ simplify_using_initial_values (class loo
   while (1)
     {
       insn = BB_END (e->src);
-      if (any_condjump_p (insn))
+      if (any_condjump_p (insn) && onlyjump_p (insn))
        {
          rtx cond = get_condition (BB_END (e->src), NULL, false, true);
 
@@ -2887,7 +2887,7 @@ check_simple_exit (class loop *loop, edg
     return;
 
   /* It must end in a simple conditional jump.  */
-  if (!any_condjump_p (BB_END (exit_bb)))
+  if (!any_condjump_p (BB_END (exit_bb)) || !onlyjump_p (BB_END (exit_bb)))
     return;
 
   ein = EDGE_SUCC (exit_bb, 0);

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